The goal of this project is to characterize the chemical composition of the myelin membrane in the central nervous system. This study has focused on the composition of the outer membrane surface. The major myelin glycoprotein has been partially purified and shown to be antigenic in rabbits. In addition a minor glycoprotein which comigrates with the proteolipid protein has been identified and characterized. Studies of the myelin glycolipids have also revealed an asymmetric distribution of the glycolipids in the myelin sheath. The measles membrane antigens are being characterized; immuno reactivity against these components is being assessed.